MANKATO - Randy Moss' mind and mouth always have been as quick and explosive as the legs that have carried him into the end zone via hyperspace 153 times in his NFL career.

Sometimes, the mind and mouth are witty, humorous and harmless. Like the time Moss was walking his dog in Minnesota and a curious reporter took a swing at small talk by asking him what the dog's breed was.

"Nunya," Moss said.

"Nunya?" the reporter asked.

"Yeah," Moss said. "Nunya ... business."

Other times, especially hard times, Moss' mind and mouth have gone much further south on him. They've taken this enigmatic man to a darker mood on and off the field and will threaten to keep him out of the Pro Football Hall of Fame despite being one of the greatest receivers the game ever has seen.

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Two years ago, Moss' mind and mouth took both his career and the career of then-Vikings coach Brad Childress on a 27-day free fall with neither side owning a parachute. It was a classic crash-and-burn that could have been sidestepped had Childress consulted some of his veterans Oct. 5, 2010, the day before he made that ill-fated trade that brought Moss back to Minnesota five years after his first stint ended with a trade to Oakland.

"Oh, yeah, I knew that relationship wasn't going to work," said cornerback Antoine Winfield, who might face Moss briefly on Friday night when his comeback with the San Francisco 49ers continues with a preseason opener against the Vikings. "They definitely were going to clash. It was just a matter of how fast."

Real fast.

"I love Randy," defensive tackle Kevin Williams said. "But I don't know what was going through his head at the time. He and Coach Childress weren't combining real well. Vinegar and oil, I guess."

Finally, in the aftermath of Moss' bizarre return to New England to play the Patriots on Nov. 1, 2010, Childress told the team Moss was being released. This, of course, followed a 28-18 loss in which Moss put forth little effort and actually quit running on a pass that should have been a touchdown.

The final straw

It also followed a postgame locker-room outburst in which Moss told owner Zygi Wilf and other team executives in no uncertain colorful terms that Childress was unfit to coach and should be fired. After that, Moss went to a podium, told reporters he'd ask himself the questions and then proceeded to praise his former coach, Bill Belichick, while criticizing Childress.

"You could tell pretty early on that he really didn't want to be with us," former Vikings linebacker Ben Leber said. "If he was going to continue doing what he was doing, it was good that he was gone."

Moss wasn't released until Nov. 2, reportedly because Wilf spent 24 hours contemplating whether he should keep Moss and fire Childress, who had violated team protocol by releasing Moss without consulting ownership. Twenty days later, Childress was fired with three years still on his contract. He was 3-7 -- including 1-3 with Moss -- only 10 months after leading the Vikings to the NFC Championship Game.

"Having Randy around for a few weeks was interesting, to say the least," linebacker Chad Greenway said. "It made things a little more fun, but it didn't help us win many games."

Greenway's most unusual memory of Moss is one shared by most of his teammates who were around at the time. It was the infamous locker room encounter with the caterer from Tinucci's the Friday before Moss was released. In an expletive-filled rant that became a national story, Moss told the caterer, "I wouldn't feed my dog this ... ," um, stuff.

"You heard the statement, 'Oh, that's Randy being Randy,' but as a professional, there are certain ways you shouldn't act," Greenway said. "And that was certainly one of them."

'Perfect situation'

Moss spent the final eight games of that season catching six passes for 80 yards and no touchdowns for the Tennessee Titans. He and Childress spent 2011 out of football. Today, Childress is the Cleveland Browns offensive coordinator, while the 35-year-old Moss is in the Bay Area receiving high praise for his talent, his close relationship with coach Jim Harbaugh and, yes, his effort level. He's battling Mario Manningham and Ted Ginn Jr. for the No. 2 receiver job opposite Michael Crabtree.

"It's a perfect situation for Randy," said Winfield, referring to the team that played host to last season's NFC Championship Game. "It's all set up for Randy to be happy on a great team. He's going to prove a lot of doubters wrong."

Winfield said he'd play with Moss "anytime, anywhere." Vikings receiver Percy Harvin echoed that sentiment while dismissing the popular notion that Moss was a bad influence on him.

Stephan Savoia, ASSOCIATED PRESS

Vikings receiver Randy Moss took part in pregame warmups before the Oct. 31, 2010, game at New England. It would be the last game he played for the Vikings.

"My favorite memory will be him teaching me how to watch film," Harvin said. "He came to my house a lot and showed me how to break down film and really study. He was so smart that we'd be watching film with the coaches and he'd ask them questions that they might not have even thought about. I don't think people realize how much of a student of the game Randy really is."

Vikings receivers coach George Stewart said the year away from the game will put Moss in the right frame of mind.

"I love his mind, a great football mind," Stewart said. "I've never been around a player who is as intelligent and as smart and has a great football sense like Randy. He was able to sit down and ask great questions. Questions that made you go, 'Mmmm, this guy may have a future after football as a coach.'"